You no longer need to be an electronics wizard to build sophisticated devices. “Makers” like the four profiled on these pages are unleashing their creativity thanks to Raspberry Pi and Arduino boards.

Two credit-card sized products are revolutionising the world of innovation: a nanocomputer called Raspberry Pi and a microcontroller known as Arduino. There appear to be no limits to the projects that can be concocted with these two tools. They range from simple utilitarian devices to gadgets at the outer edges of creativity, including drones, robotic prostheses, alarm systems, 3D printers, arcade games and Twitter-controlled coffee makers – not to mention innovative products yet to be conceived.

This development is deeply rooted in the “open-source” philosophy. Originally used in software development, this model for information- and rights-sharing is increasingly making its way to hardware projects. New do-it-yourselfers spend hours on specialised websites like Adafruit and Instructables sharing plans for their latest inventions.

Brains and brawn

Raspberry Pi and Arduino share three major features: they’re simple to use, they’re small and they’re cheap (about €20). The Arduino project, founded in 2005, completely upended the world of microcontrollers – circuit boards that process information from sensors and execute such pre-programmed commands as starting a motor.

The Raspberry Pi is a real computer stripped down to the bare essentials. It has an open-source operating system and can be connected to peripherals such as a screen, speaker, keyboard and mouse. Despite its small size, it has impressive computing power and uses very little power. It can serve as a standard PC, but makers tend to use it as a multimedia centre, server or web interface.

The two devices are often used together, notably in domotics (intelligent-home control systems). The Raspberry Pi is a control centre, receiving input from various microcontrollers (like a room thermometer) and issuing commands in response (like adjusting a thermostat). “The Pi is the brains and spinal cord, while the Arduinos are the tentacles that connect it to the world,” explains Pierre-Yves Rochat, who teaches a Massive Open Online Course (MOOC) on microcontrollers at the École Polytechnique Fédérale de Lausanne (EPFL).

Users are thrilled. “Arduino completely changed how I saw electronics,” says Sami Sabik, a French nanotechnology researcher who has been working in the Netherlands for five years. “Before, I was intimidated. Development boards were the size of a sheet of A4 paper, with cables all over the place. It took a week to get one to turn on an LED bulb. Today, it takes five minutes.” Similar boards exist, but the Italian-made Arduino is the most popular. “Actually, Arduino didn’t invent anything,” says EPFL’s Rochat. “Its creators just had the right techno­logy at the right time, a coherent package and effective communication, and it took off from there.”

A more human language

Simplification is at the heart of the revolution. “Until now, microcontrollers had to be programmed in assembly language, a complicated machine-specific language,” explains Rochat. “But Arduino innovated with a high-performance board and a wonderfully simple programming environment. By putting this added layer between the microcontroller and the user, the internal structure of the system could be forgotten. You don’t need to be an engineer to program an Arduino board. A humanities student with no electronics experience whatsoever discovered a passion for microcontrollers while taking my MOOC. Another student built a flying robot.”

Health

Immunising vaccines against blackouts

Danish students have developed a device to control the refrigeration of vital medication.

Blackouts don’t just plunge everyone into the dark. They also cut the cold chain, with catastrophic consequences for healthcare. Vaccines can become unusable if they are exposed to temperatures above or below a certain range for just a few hours. Such failure, along with other problems like expiration dates, result in the waste of more than 50% of the world’s vaccine stock, according to the World Health Organisation.

Eupry, a start-up company from the Technical University of Denmark (DTU), hopes to change all that. Using an Arduino and a Raspberry Pi, the company has developed a control device equipped with sensors that can be placed inside or on the surface of any refrigerator. “If it detects an abnormal temperature, the device alerts a technician by mobile phone,” explains company co-founder Adam Hartmann, who is also a master’s student in design and innovation.

Launched at DTU in 2012, the project is receiving support from various organisations, including UNICEF and the Clinton Foundation, which helped transport devices by boat to Nigeria for testing in March 2014. After three test versions, the first commercial model was released this summer. “The system is a response to a major issue,” says Pascal Bonnabry, head of the pharmacy at the Geneva University Hospitals. “Even so, just alerting someone in the event of a problem doesn’t guarantee that it will be solved. A malfunctioning refrigerator still has to be repaired.”

Health makers

Radiation Sensor Board
An autonomous Geiger counter

To enable Japanese residents to measure their radiation levels after the nuclear disaster in Fukushima, the Spanish company Libelium created an Arduino-based Geiger counter. Attached to wireless connection modules and a GPS, the device is an autonomous terminal that transmits readings in real time.

Incredible HQL
A lifesaving drone

Four California students have developed an autonomous drone that can carry loads of up to 22.5 kg. An Arduino is used to stabilise the machine.

Food

Smart beer

A student in the Netherlands has created a system to control fermentation temperature for his brew.

Maybe it’s because he’s Dutch that Elco Jacobs likes beer – so much, in fact, that he brews his own. “Before BrewPi, I fermented it in a sealed bucket in my kitchen,” he says. “The temperature needs to stay around 20 °C. But during the summer, it was 26 °C in my kitchen and I had to interrupt brewing for several months.” He came up with his own control system to transform a refrigerator into a fermentation chamber with a stable beer temperature. “The system is interesting because it lets you change the beer’s temperature slowly,” says Benjamin Levaux, master brewer at Les Bras­seurs in Lausanne, Switzerland.

Jacobs named his invention “BrewPi” because the device, in the shape of a transparent box, has the nanocomputer at its core. It comes equipped with three sensors – one in the beer, one in the refrigerator, one in the room – and an LCD screen. An Arduino board controls the temperature, while the Raspberry Pi logs data and provides a web interface for settings and graphs. It is accurate to a tenth of a degree. All the software and assembly instructions are open source. The only difficult part is disconnecting the thermostat in the refrigerator and installing the BrewPi in its place.

Jacobs has sold more than 600 BrewPis in 35 countries since 2012. A full kit costs about €150. “I want to give home brewers and small breweries the same level of control as the bigger ones”, says the electrical engineering student at Eindhoven University of Technology (TU/e). He has found a good niche market: independent breweries represent 5% of European beer production, and micro breweries are all the rage with hipsters. “Since the early 2000s, amateur brewers have been popping up all over the world,” says Jan Lichota of Brewers of Europe. “Thanks to the Internet, anyone can learn to produce their own hops and buy the basic ingredients.” Jacobs wants to help home brewers and small craft breweries make better beer. “Their beers are just much more interesting than those of well-known big breweries.”

Food makers

Bartendro
The robotic bartender

This impressive machine prepares cocktails that are measured down to the millilitre. A Raspberry Pi records recipes and Arduino boards control dispensers hooked up to 15 different bottles.

Dog Food Dispenser
Automatic kibble

Many hobbyists have come up with systems for dispensing pet food automatically. The most basic version involves an Arduino board programmed to release kibble twice a day using a motor.

Games

Making programming fun

Alex Klein has invented a kit for the assembly of a PC in just minutes using a Raspberry Pi.

Should programming be taught in primary school? Alex Klein thinks so. With two cofounders, this 24-year-old designer and onetime journalist launched Kano, a colourful do-it-yourself computer kit geared for young children, in January 2013. “The digital world has come to occupy an important part of our lives, but it’s mastered by less than 1% of the population,” he says. “Our project hopes to correct that.”

Kano includes a Raspberry Pi along with the usual peripherals (wireless keyboard, micro-USB, etc.). The operating system is based on Linux. It can be used to create and modify games, music and video using the principle of block programming. In Kano, “blocks” of code are put together like Lego bricks. “Kids can download Pong (the first successful video game), for example, and change everything easily, from the colour of the ball to its speed. We’re trying to make programming like playing a game.”

The project was launched after Klein met Raspberry Pi co-founder Eben Upton. “We realised that we could take that technology and do something really fun and entertaining with it,” says Klein. “Computer code is just another language. You need to have simple tools and understand how they work.”

In November 2013 Kano launched a crowd-funding campaign on Kickstarter, which raised $1.5 million. The company now has 20 employees. The first kits were delivered in August 2014 for €119 each. Several large contracts have been signed, notably with popular training institutes in Switzerland and the UK.

Game makers

Micro Arcade Machine
Scaled-down play

Jeroen Domburg of the Netherlands has built a Plexiglas mini-arcade game made from a Raspberry Pi connected to a mini-LCD screen. The console is twice the size of a cigarette lighter.

Pi-Boy
A Super Gameboy

British whiz Anton MacArthur combined a Super Nintendo controller with a broken Gameboy whose hardware was replaced with a Raspberry Pi. He added an LCD screen and re-used the original speaker.

Wearables

The body as melody

Tyler Freeman’s DrumPants transform legs into instruments, letting people make music wherever they go.

Who hasn’t found themselves at some point among a group of friends, singing and making music with whatever was at hand, even your own body? That’s what happened to California’s Tyler Freeman, a 30-year old computer scientist. “I’m a musician, like most of my friends. We were in the living room, making music by drumming on our jeans.” That was when he had the brilliant idea of creating a device that would produce a real sound when tapped. It was 2006. Eight years later, DrumPants became a reality. After a Kickstarter crowdfunding campaign that raised $74,000, the first deliveries took place in August 2014. The basic version sells for $99.

This wearable technology consists of flexible sensor-studded strips that can be worn both under and over clothing, and inside shoes. It attaches with either Velcro or straps. Added to these are a micro-USB key, an audio output and a Bluetooth-connected control box carried in a pocket. Legs can become cymbals, knees a snare drum and feet a bass drum. The combinations are end­less; the device comes with more than 100 pre-recorded virtual instruments. DrumPants can also be used to control such other applications as video games and websites.

The first prototypes were built using an Arduino board. The DrumPants team designed the newest version, which includes a smaller custom-designed chip, but the application can still be used in projects that incorporate other Arduino boards.

Freeman is already thinking ahead. “We’d like to develop a whole platform for wearable technology. Drum­Pants are our first product, but we’d like to create others, letting people control all their devices from their body.”

Wearable makers

Project Glass
Subtitled reality

British programmer Will Powell has designed a prototype for glasses that display real-time translations using two Raspberry Pis connected to Microsoft’s online translator.

Tacit
Touching the invisible

California’s Steve Hoefer has invented a haptic glove for blind people that measures the distance between its wearer and objects, translating it into pressure on the wrist. An Arduino connected to ultrasound sensors detects obstacles up to 3.5 metres away and activates two servomotors in response.

There is a whole community of adult “makers”

Eben Upton is co-founder of the Raspberry Pi Foundation, which has sold more than 3 million of the nanocomputers.

Technologist: Did you think you would do so well?

Eben Upton: Absolutely not. We were hoping to sell 10,000 units over the life of the product. The biggest surprise for us is that there is a whole community of adult “makers”, notably in our largest markets: the U.S., Germany and the UK.

T. Could Raspberry Pi and Arduino do for hardware what apps have done for software, becoming tools that allow people to develop things that suit their particular needs?

E. U. That’s an interesting analogy. Certainly the very low cost of Raspberry Pi makes it close to being “disposable” hardware in the same way that apps are “disposable” software. A big surprise for us has been that people who use a Pi in a project will often buy a new Pi for a new project, leaving the old one in the old project rather than re-using it.

T. Will you improve the Raspberry Pi?

E. U. We’re continuing to optimize the software stack on the Raspberry Pi. At some point, perhaps in 2017, we’ll need to consider introducing a new Pi, but there’s still a large amount of improvement available to us simply from software work. This has the advantage that everyone who has already bought a Pi will benefit, rather than “orphaning” them when we move to new hardware